, - C++ . , . :
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#include "stdafx.h"
#include "iostream"
float X[50][50];
int M,N,i,j;
float P=1, S=0;

int main ()
{et1: std:: cout<<"M=";
std:: cin>>M;
if (M<2||M>50) goto et1;
et2: std:: cout<<"N=";
std:: cin>>N;
if (N<2||N>50) goto et1;
for (i=0;i<M;i++)
for (j=0;j<N;j++){
std:: cout<<"X["<<i<<","<<j<<"]=";
std:: cin>>X[i][j];}
if (M==N){
for (i=0;i<M;i++)
for (j=0;j<N;j++)
if ((i>j)&&(i+j>N-1))
if (X[i][j]!=0)
P=P*X[i][j];
std:: cout<<"P="<<P<<'\n';
for (i=0;i<M;i++)
S=S+X[i][i]*X[i][N-i-1];
std:: cout<<"S="<<S<<'\n';}

return 0;
}

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