YES We show the termination of the relative TRS R/S: R: le(|0|(),y) -> true() le(s(x),|0|()) -> false() le(s(x),s(y)) -> le(x,y) minus(|0|(),y) -> |0|() minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) if_minus(true(),s(x),y) -> |0|() if_minus(false(),s(x),y) -> s(minus(x,y)) quot(|0|(),s(y)) -> |0|() quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) log(s(|0|())) -> |0|() log(s(s(x))) -> s(log(s(quot(x,s(s(|0|())))))) S: rand(x) -> x rand(x) -> rand(s(x)) -- SCC decomposition. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: le#(s(x),s(y)) -> le#(x,y) p2: minus#(s(x),y) -> if_minus#(le(s(x),y),s(x),y) p3: minus#(s(x),y) -> le#(s(x),y) p4: if_minus#(false(),s(x),y) -> minus#(x,y) p5: quot#(s(x),s(y)) -> quot#(minus(x,y),s(y)) p6: quot#(s(x),s(y)) -> minus#(x,y) p7: log#(s(s(x))) -> log#(s(quot(x,s(s(|0|()))))) p8: log#(s(s(x))) -> quot#(x,s(s(|0|()))) and R consists of: r1: le(|0|(),y) -> true() r2: le(s(x),|0|()) -> false() r3: le(s(x),s(y)) -> le(x,y) r4: minus(|0|(),y) -> |0|() r5: minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) r6: if_minus(true(),s(x),y) -> |0|() r7: if_minus(false(),s(x),y) -> s(minus(x,y)) r8: quot(|0|(),s(y)) -> |0|() r9: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r10: log(s(|0|())) -> |0|() r11: log(s(s(x))) -> s(log(s(quot(x,s(s(|0|())))))) r12: rand(x) -> x r13: rand(x) -> rand(s(x)) The estimated dependency graph contains the following SCCs: {p7} {p5} {p2, p4} {p1} -- Reduction pair. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: log#(s(s(x))) -> log#(s(quot(x,s(s(|0|()))))) and R consists of: r1: le(|0|(),y) -> true() r2: le(s(x),|0|()) -> false() r3: le(s(x),s(y)) -> le(x,y) r4: minus(|0|(),y) -> |0|() r5: minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) r6: if_minus(true(),s(x),y) -> |0|() r7: if_minus(false(),s(x),y) -> s(minus(x,y)) r8: quot(|0|(),s(y)) -> |0|() r9: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r10: log(s(|0|())) -> |0|() r11: log(s(s(x))) -> s(log(s(quot(x,s(s(|0|())))))) r12: rand(x) -> x r13: rand(x) -> rand(s(x)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11, r12, r13 Take the reduction pair: lexicographic combination of reduction pairs: 1. matrix interpretations: carrier: N^4 order: lexicographic order interpretations: log#_A(x1) = ((1,0,0,0),(1,1,0,0),(1,0,1,0),(0,1,1,1)) x1 s_A(x1) = ((1,0,0,0),(0,1,0,0),(0,0,1,0),(0,1,0,1)) x1 + (0,6,4,1) quot_A(x1,x2) = ((1,0,0,0),(0,1,0,0),(0,1,0,0),(0,0,1,0)) x1 + (0,0,2,1) |0|_A() = (0,0,1,0) le_A(x1,x2) = ((0,0,0,0),(1,0,0,0),(0,1,0,0),(0,0,0,0)) x1 + (2,2,0,2) true_A() = (1,1,1,1) false_A() = (1,3,7,3) minus_A(x1,x2) = ((1,0,0,0),(0,1,0,0),(0,1,0,0),(0,0,1,0)) x1 + (0,0,2,0) if_minus_A(x1,x2,x3) = ((1,0,0,0),(0,1,0,0),(0,1,0,0),(1,1,1,0)) x2 + ((0,0,0,0),(0,0,0,0),(0,0,0,0),(1,0,0,0)) x3 + (0,0,1,0) log_A(x1) = ((1,0,0,0),(0,1,0,0),(0,1,0,0),(0,0,0,0)) x1 + (1,0,0,1) rand_A(x1) = x1 + (1,0,1,1) 2. lexicographic path order with precedence: precedence: le > false > rand > minus > if_minus > s > log > quot > log# > true > |0| argument filter: pi(log#) = [] pi(s) = [1] pi(quot) = [] pi(|0|) = [] pi(le) = [] pi(true) = [] pi(false) = [] pi(minus) = [] pi(if_minus) = [] pi(log) = [] pi(rand) = [] The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains. -- Reduction pair. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: quot#(s(x),s(y)) -> quot#(minus(x,y),s(y)) and R consists of: r1: le(|0|(),y) -> true() r2: le(s(x),|0|()) -> false() r3: le(s(x),s(y)) -> le(x,y) r4: minus(|0|(),y) -> |0|() r5: minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) r6: if_minus(true(),s(x),y) -> |0|() r7: if_minus(false(),s(x),y) -> s(minus(x,y)) r8: quot(|0|(),s(y)) -> |0|() r9: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r10: log(s(|0|())) -> |0|() r11: log(s(s(x))) -> s(log(s(quot(x,s(s(|0|())))))) r12: rand(x) -> x r13: rand(x) -> rand(s(x)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11, r12, r13 Take the reduction pair: lexicographic combination of reduction pairs: 1. matrix interpretations: carrier: N^4 order: lexicographic order interpretations: quot#_A(x1,x2) = ((1,0,0,0),(0,1,0,0),(0,0,1,0),(0,1,0,1)) x1 + ((1,0,0,0),(0,1,0,0),(0,0,1,0),(0,1,1,1)) x2 s_A(x1) = ((1,0,0,0),(0,1,0,0),(0,0,0,0),(0,1,0,0)) x1 + (0,2,3,1) minus_A(x1,x2) = ((1,0,0,0),(0,1,0,0),(0,1,1,0),(0,1,0,0)) x1 + (0,0,1,1) le_A(x1,x2) = ((1,0,0,0),(0,0,0,0),(0,1,0,0),(0,0,1,0)) x1 + x2 + (0,0,1,0) |0|_A() = (0,1,4,0) true_A() = (0,0,1,0) false_A() = (0,1,1,0) if_minus_A(x1,x2,x3) = x2 + (0,0,2,1) quot_A(x1,x2) = ((1,0,0,0),(0,1,0,0),(0,0,1,0),(1,1,0,0)) x1 + (0,0,1,0) log_A(x1) = ((1,0,0,0),(0,1,0,0),(0,1,0,0),(0,1,1,0)) x1 rand_A(x1) = x1 + (1,1,1,1) 2. lexicographic path order with precedence: precedence: rand > quot > log > true > false > minus > if_minus > s > |0| > le > quot# argument filter: pi(quot#) = [] pi(s) = [] pi(minus) = [] pi(le) = [] pi(|0|) = [] pi(true) = [] pi(false) = [] pi(if_minus) = [2] pi(quot) = [] pi(log) = [] pi(rand) = [] The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains. -- Reduction pair. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: if_minus#(false(),s(x),y) -> minus#(x,y) p2: minus#(s(x),y) -> if_minus#(le(s(x),y),s(x),y) and R consists of: r1: le(|0|(),y) -> true() r2: le(s(x),|0|()) -> false() r3: le(s(x),s(y)) -> le(x,y) r4: minus(|0|(),y) -> |0|() r5: minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) r6: if_minus(true(),s(x),y) -> |0|() r7: if_minus(false(),s(x),y) -> s(minus(x,y)) r8: quot(|0|(),s(y)) -> |0|() r9: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r10: log(s(|0|())) -> |0|() r11: log(s(s(x))) -> s(log(s(quot(x,s(s(|0|())))))) r12: rand(x) -> x r13: rand(x) -> rand(s(x)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11, r12, r13 Take the reduction pair: lexicographic combination of reduction pairs: 1. matrix interpretations: carrier: N^4 order: lexicographic order interpretations: if_minus#_A(x1,x2,x3) = ((0,0,0,0),(0,0,0,0),(1,0,0,0),(0,1,0,0)) x1 + ((1,0,0,0),(0,1,0,0),(0,1,1,0),(0,1,1,1)) x2 + x3 false_A() = (1,0,1,2) s_A(x1) = x1 + (0,2,5,1) minus#_A(x1,x2) = ((1,0,0,0),(0,1,0,0),(0,0,0,0),(0,1,0,0)) x1 + ((1,0,0,0),(0,1,0,0),(1,0,1,0),(0,0,0,1)) x2 + (0,1,7,7) le_A(x1,x2) = ((0,0,0,0),(0,0,0,0),(1,0,0,0),(0,1,0,0)) x1 + (2,1,2,0) |0|_A() = (0,0,4,6) true_A() = (1,0,3,1) minus_A(x1,x2) = ((1,0,0,0),(0,1,0,0),(0,0,1,0),(0,0,1,0)) x1 + (0,0,0,3) if_minus_A(x1,x2,x3) = ((1,0,0,0),(0,1,0,0),(0,0,1,0),(0,0,1,0)) x2 quot_A(x1,x2) = ((1,0,0,0),(0,1,0,0),(0,0,1,0),(1,1,0,0)) x1 + ((0,0,0,0),(0,0,0,0),(1,0,0,0),(0,0,0,0)) x2 + (0,0,0,7) log_A(x1) = ((1,0,0,0),(1,1,0,0),(1,1,1,0),(1,0,0,0)) x1 + (1,0,0,7) rand_A(x1) = x1 + (1,1,1,1) 2. lexicographic path order with precedence: precedence: rand > quot > minus > if_minus > le > false > log > true > if_minus# > minus# > s > |0| argument filter: pi(if_minus#) = 3 pi(false) = [] pi(s) = [] pi(minus#) = 2 pi(le) = [] pi(|0|) = [] pi(true) = [] pi(minus) = [] pi(if_minus) = [] pi(quot) = [] pi(log) = [] pi(rand) = [] The next rules are strictly ordered: p1, p2 We remove them from the problem. Then no dependency pair remains. -- Reduction pair. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: le#(s(x),s(y)) -> le#(x,y) and R consists of: r1: le(|0|(),y) -> true() r2: le(s(x),|0|()) -> false() r3: le(s(x),s(y)) -> le(x,y) r4: minus(|0|(),y) -> |0|() r5: minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) r6: if_minus(true(),s(x),y) -> |0|() r7: if_minus(false(),s(x),y) -> s(minus(x,y)) r8: quot(|0|(),s(y)) -> |0|() r9: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r10: log(s(|0|())) -> |0|() r11: log(s(s(x))) -> s(log(s(quot(x,s(s(|0|())))))) r12: rand(x) -> x r13: rand(x) -> rand(s(x)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11, r12, r13 Take the reduction pair: lexicographic combination of reduction pairs: 1. matrix interpretations: carrier: N^4 order: lexicographic order interpretations: le#_A(x1,x2) = ((1,0,0,0),(0,1,0,0),(0,0,0,0),(0,1,1,0)) x1 + ((1,0,0,0),(0,1,0,0),(0,0,1,0),(0,1,1,1)) x2 s_A(x1) = x1 + (0,2,1,1) le_A(x1,x2) = x2 + (2,2,2,2) |0|_A() = (0,1,3,4) true_A() = (1,1,1,1) false_A() = (1,4,6,5) minus_A(x1,x2) = x1 + ((0,0,0,0),(0,0,0,0),(1,0,0,0),(0,0,0,0)) x2 + (0,0,2,6) if_minus_A(x1,x2,x3) = ((1,0,0,0),(0,1,0,0),(0,0,1,0),(1,1,0,1)) x2 + ((0,0,0,0),(0,0,0,0),(1,0,0,0),(1,1,0,0)) x3 + (0,0,1,2) quot_A(x1,x2) = ((1,0,0,0),(0,1,0,0),(0,1,1,0),(0,1,1,1)) x1 + ((0,0,0,0),(0,0,0,0),(1,0,0,0),(0,0,0,0)) x2 + (0,0,1,1) log_A(x1) = ((1,0,0,0),(0,1,0,0),(1,0,0,0),(0,1,0,0)) x1 + (1,0,2,0) rand_A(x1) = x1 + (1,0,1,1) 2. lexicographic path order with precedence: precedence: if_minus > rand > le > log > s > quot > true > minus > |0| > false > le# argument filter: pi(le#) = [] pi(s) = [] pi(le) = [] pi(|0|) = [] pi(true) = [] pi(false) = [] pi(minus) = [] pi(if_minus) = [2] pi(quot) = [1] pi(log) = [] pi(rand) = [] The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains.