Math # extended Euclid POJ 1061&2115&2891

Winter vacation To do the problem, first paste at that time write code.

POJ 1061

#include <iostream>#include<cstdio>typedefLong LongLL;using namespacestd;voidEXTEND_GCD (LL a,ll b,ll &d,ll &x,ll &y) {    if(b==0) {D=A; X=1, y=0; }    Else{EXTEND_GCD (b,a%b,d,y,x); Y-=x* (A/b); }}intMain () {LL x,y,m,n,l;  while(SCANF ("%i64d%i64d%i64d%i64d%i64d", &x,&y,&m,&n,&l)! =EOF)        {LL d,xx,yy; EXTEND_GCD (n-m,l,d,xx,yy); if(x-y)%d==0) {LL P=l/D; XX= (x-y)/d*xx; XX= (xx%p+p)%p; printf ("%i64d\n", XX); }        Elseprintf"impossible\n"); }    return 0;}

POJ 2115

#include <iostream>#include<cstdio>#include<cmath>#include<algorithm>#include<cstring>#include<string>#include<cstdlib>#include<vector>#include<stack>#include<map>using namespaceStd;typedefLong LongLl;ll extend_gcd (ll a,ll b,ll&x,ll &y) {  //return D=GCD (a,n);    if(b==0) {x=1, y=0; returnA; }    Else{ll T=EXTEND_GCD (b,a%b,x,y); ll xx=x,yy=y; X=yy; Y=xx-(A/b) *yy; returnT; }}intMain () {ll a,b,c,k,x,y;  while(~SCANF ("%i64d%i64d%i64d%i64d",&a,&b,&c,&k)) {if(a==0&&b==0&&c==0&&k==0) Break; ll a=c,b=b-a,n= (LL)1<<k;//n=2^kll d=EXTEND_GCD (a,n,x,y); if(b%d!=0)//no solution to the equationprintf"forever\n"); Else{x= (x* (b/d))%n;//x is the minimum solution of Equation ax=b (mod n)x= (x (n/d) +n/d)% (N/D);//x is the smallest integer solution of equation ax=b (mod n)printf"%i64d\n", x); }    }    return 0;}

POJ 2891

#include <iostream>#include<cstdio>using namespaceStd;typedefLong Longll;voidEXTEND_GCD (ll a,ll b,ll &d,ll &x,ll &y) {    if(b==0) {D=A; X=1, y=0; }    Else{EXTEND_GCD (b,a%b,d,y,x); Y-=x* (A/b); }}intMain () {intK;    ll A1,r1,a,r;  while(~SCANF ("%d",&k)) {scanf ("%i64d%i64d",&a1,&R1); intflag=1;  for(intI=2; i<=k;i++) {scanf ("%i64d%i64d",&a,&R);            ll D,x,y;            EXTEND_GCD (A1,a,d,x,y); if((R-R1)%d!=0) Flag=0; LL P=a/D; X= (R-R1)/d*x; X= (x%p+p)%p; R1=a1*x+R1; A1=a1* (A/d); }        if(flag) printf ("%i64d\n", R1); Elseprintf"-1\n"); }    return 0;}

Math # extended Euclid POJ 1061&2115&2891